Connecting device for tubular elements

ABSTRACT

A connecting device for tubular elements ( 1 ), in order to carrying out modular structures, includes: 
         insert means ( 22 ) each having an expandable portion ( 2 ) and a head ( 3 );    shells ( 9 ) each provided with a plurality of housing ( 10 ) having a shape approximately complementary to the head ( 3 );    fixing means of head ( 3 ) to a related housing ( 10 ).        

     In a locking condition of an insert mean ( 22 ) into an end of the tubular element ( 1 ), the expandable portion ( 2 ) is inserted into said end and it is expanded.  
     In a connection condition of the tubular element ( 1 ) to the shell ( 9 ), the head ( 3 ) in the locking condition with the tubular element ( 1 ) is engaged in a related housing ( 10 ) of the shell and fixed to this latter by means of the fixing means.

TECHNICAL FIELD

The present invention refers to connecting devices for modularstructures, particularly relates to a connecting device for tubularelements which allows the quick connection of said elements withoutrequiring assembly holes made in these latter.

BACKGROUND ART

There are known connecting devices requiring the previous transversaldrilling of tubular element ends in order to connect said tubularelements and carry out structures for shelves, tables, exhibitors, andthe like. Consequently the lengths of the elements must be predefinedduring the manufacturing phase, since they cannot be easily changed.

There are known connecting devices allowing the connection betweentubular elements without fixing holes, but said connecting devices areexternal with respect to said tubular elements.

The main drawback of said known devices consists in that they are bulkyand well visible, so conditioning the aesthetics of the whole structure.Further drawback of said known devices consists in that it is necessaryto loosen several connecting devices, in order to modify the position ofan element.

Document DE 94 13 840 U discloses a connecting device suitable fortubular elements fit for constructing modular structures, wherein saidconnecting device includes insert means having an expandable portion anda head, shells each provided with a plurality of housing having a shapeapproximately complementary to the head; fixing, means to fix the headto a related housing.

DISCLOSURE OF THE INVENTION

The main object of the present invention is to propose a connectingdevice for tubular elements having small dimension and providing fastconnection between the tubular elements, without the necessity to drillthe end portion of said elements. The length of the tubular elements canbe easily fit to the customer's demands, also during the assemblage.

The connecting device that will be described is constituted by anelement having an expandable portion to be inserted into the tubularelement to be connected and a truncated-pyramidal head that protrudestherefrom and is inserted into the corresponding housing of a suitablemulti-arm shell. The truncated-pyramidal head has an axial hole for anexpansion screw and side seats, in which dowel ends are inserted. Saiddowels, screwed into holes carried out in the arms of the shell, stopthe elements to be connected.

The objects above-mentioned are achieved according with the content ofthe claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The characteristics of the invention are underlined in the following,with particular reference to the attached drawings, in which:

FIG. 1 shows an axonometric exploded view of the connecting deviceobject of the present invention in association with a tubular element;

FIG. 2 shows a front view of an insert mean of the connecting device ofFIG. 1;

FIG. 3 shows a side view of the insert mean of FIG. 2;

FIGS. 4 and 5 show respectively a front view and a side view of a cap ofFIG. 2 connecting device;

FIG. 6 shows an axonometric view of a shell of FIG. 1 device with threearms positioned along a plane;

FIGS. 7 and 8 show respectively a side view and a front view of the FIG.6 shell;

FIG. 9 shows a plan sectional view of the shell of FIG. 6;

FIG. 10 shows an axonometric view of a shell with three arms positionedon different planes;

FIGS. 11 and 12 show respectively a plan and a side view of the FIG. 10shell;

FIG. 13 shows a front section view of the shell of FIG. 10;

FIG. 14 shows an axonometric view of a possible structure constituted bytubular elements connected by means of the connecting devices object ofthe present invention;

FIGS. 15 and 16 show respectively a front view and a side view of theFIG. 14 structure.

BEST MODE OF CARRYING OUT THE INVENTION

With reference to FIGS. 1-9, numeral 1 indicates a tubular element to beconnected to the connecting device to carry out a modular structure,exemplified in FIGS. 14-16. The connecting device includes a pluralityof insert means 22, each having an expandable portion 2 and a head 3approximately truncated-pyramidal shaped.

The connecting device comprises a plurality of shells 9 each providedwith a plurality of protruding arms, each having a housing 10 with ashape approximately complementary to the head 3.

The head 3 has an axial hole 4 for a screw 5, engaged in a threaded hole6 of a cap 7 having inclined surfaces internally sliding over elasticfins of the expandable portions 2.

Each arm of shells is provided with fixing means including dowels 12each screwed in a related threaded hole 11, carried out in the shell 9,and engaged in a related side seat 13 of the head 3.

The threaded holes 11 are perpendicular to the longitudinal axis of therelated housing.

Alternatively, the invention provides that the threaded holes 11 areinclined.

The expandable portion 2 and the internal cavity of tubular elements arecomplementary and polygonal shaped and it is also provided that they canbe circular or elliptical shaped.

The insert mean 22 includes a stop rim 8 which separates the expandableportion 2 and the truncated-pyramidal head 3, fit for matching the edgeof the end of the tubular element.

The shell 9 has three perpendicular arms, and related housings 10, lyingon a plane. The variant of shell 9 of FIGS. 10-13 has threeperpendicular arms defining three perpendicular axis.

The invention provides also shells 9 having a number of arms from two upto more than six, and defining angles of 180°, 90°, 60°, 45° and/orothers.

The operation of the device provides that the expandable portion 2 isinserted into the cavity of the tubular element 1 up to the contactbetween the edges of the end of this latter and the stop rim 8. Therotation of the screw 5 causes the movement of the cap 7 and theexpansion of the fins of the expandable portion 2 against the internalwall of the tubular element 1, reaching a locking condition between theinsert mean 22 and the tubular element 1.

The head 3 of the insert mean 22, in the locking condition with thetubular element 1, is engaged in a related housing 10 of the shell andfixed to this latter by means of the fixing means reaching a connectioncondition of the tubular element 1 to the shell 9.

1) Connecting device for tubular elements (1) fit for carrying outmodular structures, it includes: insert means (22) each having anexpandable portion (2) and a head (3); the expandable portion (2) isinsertable into one end of one of the tubular element (1) and it isexpandable to be locked therein, shells (9) each provided with aplurality of housing (10) having a shape approximately complementary tothe head (3); the head (3) is engageable in a related housing (10) ofthe shell; fixing means to fix the head (3) to a related housing (10);said device being characterized in that: the head (3) and the housing(10) are approximately truncated-pyramidal shaped. 2) Connecting deviceaccording to claim 1 characterized in that the head (3) has an axialhole (4) for a screw (5), engaged in a threaded hole (6) of a cap (7)having inclined surfaces internally sliding over fin of the expandableportion (2), causing the expansion of this latter and thus the lockingof the insert mean (22) inside the tubular element (1) in the lockingcondition. 3) Connecting device according to claim 1 characterized inthat the fixing means include dowels (12) each screwed in a relatedthreaded hole (11), carried out in the shell (9), and engaged in arelated side scat (13) of head (3) locked to the tubular element (1) inthe connection condition of this latter to the shell (9). 4) Connectingdevice according to claim 1 characterized in that each housing (10) ofthe shell (9) is carried out in a related arm protruding from the shell(9). 5) Connecting device according to claim 1 characterized in that theexpandable portion (2) and the internal cavity of tubular elements arecomplementary and are approximately polygonal or circular or ellipticalshaped. 6) Connecting device according to claim 1 characterized in thatthe insert mean (22) includes a stop rim (8) which separates theexpandable portion (2) and the truncated-pyramidal head (3), fit forcontacting the edge of the end of the tubular element (1) in the lockingcondition of the insert mean (22) into the end of the tubular element(1). 7) Contacting device according to claim 3 characterized in that thethreaded holes (11) are perpendicular or inclined with respect to thelongitudinal axis of the related housing (10).